What is the innervation of the spleen?
The spleen is innervated by autonomic nerves from the celiac plexus, which supply the spleen with both sympathetic and parasympathetic nerves. These nerves form the splenic plexus which reaches the splenic hilum traveling along the splenic artery and its branches.
What is the blood supply of spleen?
The splenic artery supplies blood to the spleen. This artery is the largest branch of the celiac trunk and reaches the spleen’s hilum by passing through the splenorenal ligament. It divides into multiple branches at the hilum.
Where blood vessels and nerves enter the spleen?
The capsule is deeply indented in one part of the spleen to form the hilus where blood vessels, lymphatic vessels and nerves enter and exit. Arterial vessels branch into the trabeculae and from there enter the pulp or parenchyma of the organ. Veins also run in the trabeculae, entering from the pulp.
How does blood flow in the spleen?
The splenic artery brings blood to the spleen from the heart. Blood leaves the spleen through the splenic vein, which drains into a larger vein (the portal vein) that carries the blood to the liver. The spleen has a covering of fibrous tissue (the splenic capsule) that supports its blood vessels and lymphatic vessels.
What is the sympathetic supply of the spleen?
The spleen receives sympathetic innervation arising from the mesenteric/celiac ganglia. The fibers approach the spleen with the splenic nerve, enter at the pilar region, and distribute themselves along the blood vessels, innervating them and the smooth muscle cells, and extend into areas populated by immune cells.
Does the spleen have parasympathetic innervation?
Thus, neuroanatomical and neurochemical evidence demonstrates that neural innervation of the spleen is entirely sympathetic in origin, and indicates further that there is no evidence for parasympathetic or sensory input to the spleen.
What is a spleen and its function?
The spleen has some important functions: it fights invading germs in the blood (the spleen contains infection-fighting white blood cells) it controls the level of blood cells (white blood cells, red blood cells and platelets) it filters the blood and removes any old or damaged red blood cells.
Does all blood flow through spleen?
Blood flow through the spleen is very high, about 5-10% of the cardiac output and 150 mL/min (ranging from 100 to 1200 mL/min) in the resting state.
How do lymphocytes enter the spleen?
While antigen can reach lymph nodes via afferent lymphatics, either taken up by dendritic cells or by drainage in lymph fluid, lymphocytes enter this organ via the specialized high endothelial venules (HEV).